package com.kexio.auth.metrics;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
import org.springframework.stereotype.Component;

/**
 * 统一的空实现指标提供者
 * 
 * 实现UnifiedSecurityMetrics接口的空操作版本，替代原有的：
 * - NoopAuthorizationMetrics
 * - NoopSecurityMetrics  
 * - NoopSecurityOpsMetrics
 * - NoopMetricsProvider
 * 
 * 特性：
 * - 统一的指标接口实现
 * - 调试级别的日志记录
 * - 零性能开销的空操作
 * - 条件化装配，可被真实实现替代
 * 
 * @author Kexio Team
 * @since 1.0.0
 */
@Component("unifiedNoopMetricsProvider") 
@ConditionalOnMissingBean(UnifiedSecurityMetrics.class)
public class UnifiedNoopMetricsProvider implements UnifiedSecurityMetrics {
    
    private static final Logger logger = LoggerFactory.getLogger(UnifiedNoopMetricsProvider.class);
    
    // ==================== 认证指标 ====================
    
    @Override
    public void onLoginSuccess(String tenantId, String userId) {
        logger.debug("📊 [No-op] Login成功: tenant={}, user={}", tenantId, userId);
    }
    
    @Override
    public void onLoginFailure(String tenantId, String username, String reason) {
        logger.debug("📊 [No-op] Login失败: tenant={}, username={}, reason={}", tenantId, username, reason);
    }
    
    @Override
    public void onRefreshSuccess(String tenantId, String userId) {
        logger.debug("📊 [No-op] 令牌刷新成功: tenant={}, user={}", tenantId, userId);
    }
    
    @Override
    public void onRefreshFailure(String tenantId, String userId, String reason) {
        logger.debug("📊 [No-op] 令牌刷新失败: tenant={}, user={}, reason={}", tenantId, userId, reason);
    }
    
    @Override
    public void onLogout(String tenantId, String userId, boolean success) {
        logger.debug("📊 [No-op] 用户登出: tenant={}, user={}, success={}", tenantId, userId, success);
    }
    
    // ==================== 权限评估指标 ====================
    
    @Override
    public void onExpressionEvaluated(String tenantId, String userId, String expression, boolean success, long elapsedMs) {
        logger.debug("📊 [No-op] 权限表达式评估: tenant={}, user={}, expression={}, success={}, elapsed={}ms", 
            tenantId, userId, truncateExpression(expression), success, elapsedMs);
    }
    
    @Override
    public void onExpressionError(String tenantId, String userId, String expression, String error) {
        logger.debug("📊 [No-op] 权限表达式错误: tenant={}, user={}, expression={}, error={}", 
            tenantId, userId, truncateExpression(expression), error);
    }
    
    // ==================== 会话指标 ====================
    
    @Override
    public void onSessionCreate(String tenantId, String userId, boolean success, long elapsedMs) {
        logger.debug("📊 [No-op] 会话创建: tenant={}, user={}, success={}, elapsed={}ms", 
            tenantId, userId, success, elapsedMs);
    }
    
    @Override
    public void onSessionUpdate(String sessionId, boolean success, long elapsedMs) {
        logger.debug("📊 [No-op] 会话更新: sessionId={}, success={}, elapsed={}ms", 
            truncateSessionId(sessionId), success, elapsedMs);
    }
    
    @Override
    public void onSessionTerminate(String tenantId, String userId, String sessionId, boolean success, long elapsedMs) {
        logger.debug("📊 [No-op] 会话终止: tenant={}, user={}, sessionId={}, success={}, elapsed={}ms", 
            tenantId, userId, truncateSessionId(sessionId), success, elapsedMs);
    }
    
    @Override
    public void onSessionTerminateAll(String tenantId, String userId, int terminatedCount, long elapsedMs) {
        logger.debug("📊 [No-op] 批量会话终止: tenant={}, user={}, count={}, elapsed={}ms", 
            tenantId, userId, terminatedCount, elapsedMs);
    }
    
    // ==================== JWT撤销指标 ====================
    
    @Override
    public void onJwtRevoke(String tenantId, String scope, int count, boolean success, long elapsedMs) {
        logger.debug("📊 [No-op] JWT撤销: tenant={}, scope={}, count={}, success={}, elapsed={}ms", 
            tenantId, scope, count, success, elapsedMs);
    }
    
    @Override
    public void onJwtBlacklistCheck(String tenantId, String scope, boolean success, long elapsedMs) {
        logger.debug("📊 [No-op] JWT黑名单检查: tenant={}, scope={}, success={}, elapsed={}ms", 
            tenantId, scope, success, elapsedMs);
    }
    
    @Override
    public void onJwtBlacklistCleanup(String tenantId, int scannedCount, long elapsedMs) {
        logger.debug("📊 [No-op] JWT黑名单清理: tenant={}, scanned={}, elapsed={}ms", 
            tenantId, scannedCount, elapsedMs);
    }
    
    // ==================== 缓存指标 ====================
    
    @Override
    public void onCacheAccess(String cacheType, String tenantId, boolean hit, long elapsedMs) {
        logger.debug("📊 [No-op] 缓存访问: type={}, tenant={}, hit={}, elapsed={}ms", 
            cacheType, tenantId, hit, elapsedMs);
    }
    
    @Override
    public void onCacheEviction(String cacheType, String tenantId, int evictedCount, long elapsedMs) {
        logger.debug("📊 [No-op] 缓存失效: type={}, tenant={}, evicted={}, elapsed={}ms", 
            cacheType, tenantId, evictedCount, elapsedMs);
    }
    
    // ==================== 安全事件指标 ====================
    
    @Override
    public void onSecurityEvent(String eventType, String tenantId, String userId, String severity, String details) {
        logger.debug("📊 [No-op] 安全事件: type={}, tenant={}, user={}, severity={}, details={}", 
            eventType, tenantId, userId, severity, truncateDetails(details));
    }
    
    @Override
    public void onPerformanceWarning(String operation, String tenantId, long elapsedMs, long threshold) {
        logger.debug("📊 [No-op] 性能警告: operation={}, tenant={}, elapsed={}ms, threshold={}ms", 
            operation, tenantId, elapsedMs, threshold);
    }
    
    // ==================== Helper Methods ====================
    
    /**
     * 截断权限表达式用于日志记录
     */
    private String truncateExpression(String expression) {
        if (expression == null) return "null";
        if (expression.length() <= 50) return expression;
        return expression.substring(0, 47) + "...";
    }
    
    /**
     * 截断会话ID用于日志记录
     */
    private String truncateSessionId(String sessionId) {
        if (sessionId == null) return "null";
        if (sessionId.length() <= 20) return sessionId;
        return sessionId.substring(0, 8) + "..." + sessionId.substring(sessionId.length() - 8);
    }
    
    /**
     * 截断详情信息用于日志记录
     */
    private String truncateDetails(String details) {
        if (details == null) return "null";
        if (details.length() <= 100) return details;
        return details.substring(0, 97) + "...";
    }
    
    // ==================== Provider Information ====================
    
    /**
     * 获取提供者信息
     */
    public String getProviderInfo() {
        return "UnifiedNoopMetricsProvider{" +
               "interface=UnifiedSecurityMetrics, " +
               "mode=debug-logging, " +
               "performance=zero-overhead}";
    }
    
    /**
     * 检查提供者是否处于活动状态
     */
    public boolean isActive() {
        return true;
    }
    
    /**
     * 获取支持的指标类型
     */
    public String[] getSupportedMetricTypes() {
        return new String[]{
            "authentication",    // 认证指标
            "authorization",     // 权限评估指标  
            "session",          // 会话指标
            "jwt",              // JWT撤销指标
            "cache",            // 缓存指标
            "security",         // 安全事件指标
            "performance"       // 性能指标
        };
    }
}
